Guide for printing



Jan- 30, 1962 L. c. cli-:RULLO 3,018,729

GUIDE FOR PRINTING /\Filed Sept. 2, 1960 F /f States 3,018,729 GUIDE FOR PRINTING Louis C. Cerullo, 4180 Clarendon, Chicago, Ill. Filed Sept. 2, 1960, Ser. No. 53,721 Claims. (Cl. 101-415) in connection with multicolor silk screen printing equipment.

It is the principal object of the present invention to facilitate the positioning of stock to be printed in a printing machine and thereby substantially reduce the time and expense involved both in setting up the machine for printing and in the subsequent printing operation.

It is a related object of the present invention to provide an improved adjustable guide or stop for use in positioning sheet material to be printed on a table or support in a printing machine. A more speciiic object is to provide a device of the foregoing character which eliminates the hit-and-miss or trial-and-error adjustment involved in locating sheet stock for printing, and thereby avoid waste of stock and loss of valuable labor and printing time.

Another object of the invention is to provide a device of the above type which, when mounted on a printing machine table or support, accurately locates the edge position of the stock to be printed and which can be rapidly and easily adjusted without removing the device from the support table.

A further object is to provide a device of the above type which embodies indicating or indexing means for facilitating the adjustment of the position of the material to be printed.

Still another object of the present invention is to provide a device of the foregoing characteristics which is inexpensive to produce, is simple to use, and is readily mounted to the support table of the printing machine without interfering with or hindering the printing operation.

Still a further object of the invention is to provide a positioning device of the foregoing character which is capable of use with a Wide variation of sizes and thicknesses of printing stocks, which can be readily adjusted to accommodate such stocks, and which is particularly suitable and adapted for use with multicolor printing operations.

Illustrative embodiments of the present invention having the foregoing objects and advantages, as well as having other objects and advantages which will become apparent as the following description proceeds, are shown in the accompanying drawing wherein:

FIGURE l is an elevation view, generally schematic in nature, of a silk screen printing mechanism including a support table on which sheet positioning devices embodying the present invention are mounted.

FIG. 2 is a plan view of a support table mounting devices embodying the present invention.

FIG, 3 is a plan view of a sheet positioning device embodying the present invention.

FIG. 4 is a section View taken substantially in the plane of line 4 4 of FIG. 3.

FIG. 5 is a modified form of a sheet positioning device embodying the present invention.

FIG. 6 is a section view taken substantially in the plane of line 6 6 of FIG. 5.

The present invention resides in a sheet positioning device or guide for use on a printing machine such as a silk screen printing machine illustrated in FIG. l. This device, two modiiied forms of which are illustrated in the f atent 'ice drawing is indicated generally at 10 on FIG. 2, and is shown mounted on a printing machine which supports a table 11 for printinga sheet of printing stock 12. To position the sheet 12 accurately and hold it in place during a subsequent printing operation, three positioning devices or guides 10 are conventionally employed, two being located at the bottom of the sheet and defining the bottom edge and one or more being positioned along one side of the sheet, conventionally lthe left side of the sheet, although the position of the side guide will depend upon the manner in which the sheet 12 is to be inserted into the machine.

The elements of an illustrative silk screen type printing machine are shown schematically in FIG. l and comprise a base 14 supporting the table 11 carrying the positioning guides 10 and the sheet `12.. A silk screen frame 15 is hinged by suitable hinge means 16 at one side of the base 14 and includes the conventional squeegee 18 and lever mechanism indicated generally at 19. In use, the positioning guides 10 are mounted in place on the table 11 to hold the sheet 12 in position for printing. The manner of mounting and adjusting the positioning guides will be described in more detail below. A silk screen is mounted in the frame 15. For printing, the screen frame 15 is lowered to hold the screen against the sheet to be printed and the squeegee 18 is moved across the screen by the lever mechanism 19 carrying ink with it and squeezing the ink through the silk screen onto the sheet thereby forming an image. With the squeegee at the upper end of its travel and with the frame 15 lowered against the table, the mechanism occupies the position shown in phantom in FIG. l.

Turning now to the present invention as embodied in the positioning devices indicated generally at 10 in FIG. 2 and illustrated in detail in FIGS. 4-6, inclusive, these devices embody means for accurately positioning and locating the sheet of stock to be printed on the printing table 12, Which means can be readily adjusted to aline the sheet stock 1K2 with respect to the frame 15 and the silk screen. It is desirable that this adjustment be readily accomplished from a single trial printing. Accordingly, the positioning device 10l comprises a generally circular, ilattened structure formed preferably of sheet plastic material such as a phenol formaldehyde laminate. The device includes a central portion in the form of a circular disc 20 adapted to be attached to the table 11. To this end suitable apertures 21 are provided therein for the receipt of fasteners 22, or alternatively, the disc 20 may be glued directly to the table 11 which is conventionally provided with a protective sheet or mat (not shown).

Surrounding the central disc 20 and serving as the sheet guide stop is an outer annular member 24 having a circular outer periphery 25 and a central opening or aperture 26 adapted to iit snugly around the periphery of the central disc 20. In order to obtain adjustment of the ring for sheet positioning purposes, the center opening dening the annulus or ring is eccentric or oit-center so that, as a result, the width of the ring 24 varies uniformly from a narrow portion shown at the left of FIG. 3, `to a relatively wider portion shown at the right in FIG. 3. It can be readily observed that the width of the ring 24 with respect to a single selected radius of the central disc 20 can be easily and rapidly varied by simply rotating the ring 24 with respect to the disc. In other words, the distance between the edge of the central disc 20 and the outer edge 25 of the ring 24 along a selected radius of the central disc can be varied from a minimum width to a maximum width, depending upon the eccentricity of the central aperture 26 in the ring 24. It is the eccentric positioning of `the ring on the central disc `and the resulting variation in ring width that facilitates the adjustment of the position of a sheet in the printing machine when this invention is employed as a sheet guide on a printing table. I

For obtaining a snug engagement between the ring 24 and the central disc 20 in order to prevent the parts from slipping relative to one another during a printing operation, means are provided for holding the two parts snugly together. One illustrative.construction is shown in -FIGSt 3 and 4. In this form of construction, the center opening 26 the ring is formed slightly smaller 'than the size of the disc 20, and a radial slit 28 is made in the narrow portion of the ring. This slit allows the 'ring to be slightly expanded to tit over the disc 20 and the natural resilience of the ring 24 holds it snugly and securely in position on the disc 20.

An alternative construction for mounting the ring in snugly fitting engagement with the central disc is shown in FIGS 5 and 6 and this construction reduces the danger that the ring will drop off of the disc and be lost. In describing this Ymodified form of the invention, reference characters similar to those employed above will be used with the distinguishing suffix a. In order to prevent separation of the ring from the disc, the adjoining edges of the parts, that is the outer edge of the central disc 20a and the inner'edge of the central opening 26a of the ling, are correspondingly tapered inwardly as shown in FIG. 6 so that when the central disc 20a is secured to the table 11, the ring cannot slip 01T but rather is held by the tapered edges. It should also be understood that a similar construction might be applied to the form of device illustrated in FIG. 3.

In order to prevent unintended slipping of the parts shown in FIGS. 5 and 6, the central aperture 26 of the ring is cut slightly smaller than the periphery of the central disc 20 so that the disc and ring fit tightly together as described above. The desired resilience is provided in this modification by a pair of arcuate slots 30 cut in the central disc 20a adjacent the periphery thereof leaving marginal edge portions 31 which, because of the natural resilience of the material, can be compressed to a slight degree radially inwardly and serve, in the manner of springs, to hold the disc 20a and the ring 24a tightly or snugly together. As in the previously described modification, suitable apertures 21a are provided in the central disc for receiving fasteners 22a or the central disc may be glued to the table surface.

To facilitate the adjustment of the ring with respect to the disc, there is desirably provided means for engaging or gripping the ring. One illustrative means comprises simply a hole or depression 321, 32a in the surface of the ring which can be engaged by a sharp pointed implement and the latter used to slide the ring around the central disc to obtain the desired adjustment.

For use with thin sheet stock, the outer peripheral edge 25a of the ring is provided with a recess or notch 34 which results in an overhanging shoulder 35. The thin sheet stock is positioned within the notch and is held in place by the shoulder 35 so that it is prevented from sliding up over the edge of the positioning guide 10, 10a.

To use either form of the positioning guide described above, three such guides 10 are positioned on the table 11 as shown in FIG. 2. These devices are positioned in approximately the correct location for supporting the sheet stock 12 for printing. The sheet is inserted and a trial printing is made. The amount of correction needed to center or otherwise locate the printing in the desired position on successive sheets is then readily determined by a simple measurement. The positioning guides can then be readily and easily adjusted to accommodate the desired correction.

To facilitate the adjustment of the guides, the positioning devices embodying the invention includes indicia which serve to indicate the amount of correction obtained upon a given rotation of the outer ring. To this end,

one of the parts, the center disc 20 or 20a as shown in the drawings, includes a xed reference mark such as a narrow-head indicated at 33. The other member, the outer ring 24 as shown in the drawings, includes graduated indicia I39 arranged and marked according to the thickness of the ring at that point.

Knowing the amount of correction needed to position the printing on the sheet 12, it is a simple matter to increase or decrease the thickness of the ring an amount corresponding to the correction needed. It will be appreciated that with the indicia means and the ring construction shown and described, the positioning guides will be located on the table 11 with the arrows 38 of the central disc in a direction generally parallel to the adjacent edge of the sheet to be printed, as shown in FIG. 2. The ring '24 can then be rotated either to increase or decrease lthe radial width and thereby shift the position of the sheet 12.

The invention defines particular utility in connection with multicolor silk screen printing. For example, the irst color printing is applied to the sheets after setting the positioning guides as described above. When the screen is changed to provide a second color, a trial printing is again made and the amount of correction is at once obvious. The guides 10 are then adjusted in a matter of seconds and the machine is then ready for the next run. This can be repeated for as many color overlays as desired, thereby saving a substantial amount of labor, time and expense in setting up the machine for each color run.

It will be appreciated by those skilled in the art that the invention is not necessarily limited to use with a silk screen machine but will iind utility in connection with letter press printing machines and other similar printing operations. While certain illustrative forms of the invention have been shown in the drawing and described in detail, it should be understood that there is no intention to limit the invention to the specificforms disclosed. On the contrary the intention is to cover all modifications, alternative constructions, equivalents and uses falling within the spirit and scope of the invention as expressed in the appended claims.

I claim as my invention:

1. For use in locating sheet material on a support for printing, an adjustable guide comprising a disc fastenable to the support, and a split ring of uniformly varying width snugly surrounding said disc and adjustable `relative thereto for selectively varying the distance between the edge of said disc and the edge of said ring along a selected disc radius.

2. For use in locating sheet material on a support for printing, an adjustable guide comprising a disc fastenable to the support, and a split ring of uniformly varying width having an inner edge snugly engaging the outer edge of said disc and adjustable relative thereto for selectively varying the distance between the outer edge of said disc and the outer edge of said ring along a selected disc radius, said snugly engaging edges being correspondingly tapered to prevent said ring from slipping off of said disc.

3. For use in locating sheet material on a support for printing, an adjustable guide comprising a disc fastenable to the support, and a ring of uniformly varying width having an inner edge engaging the outer edge of said disc and adjustable relative thereto for selectively varying the distance between the outer edge of said disc and the outer edge of said ring along a selected disc radius, said disc having arcuate slots cut therein adjacent the periphery thereof and defining resilient marginal edge portions for snugly engaging said ring to hold the same in a selected position of adjustment.

4. For use in locating sheet material on a support for printing, an adjustable guide comprising a disc fastenable to the support, and a ring of uniformly varying width having an inner edge engaging the outer edge of said disc and adjustable relative thereto for selectively varying the distance between the outer edge of said disc and the outer edge of said ring along a selected disc radius, said disc having arcuate slots cut therein adjacent the periphery thereof and defining resilient marginal edge portions for snugly engaging said ring to hold the same in a selected position of adjustment, said snugly engaging edges being correspondingly tapered to prevent said ring from slipping off of said disc.

5. For use in locating sheet material on a support for printing, an adjustable guide comprising a disc fastenable to the support, and a ring of uniformly varying width having an inner edge engaging the outer peripheral edge of said disc and adjustable relative thereto for selectively varying the distance between the edge of said disc and the edge of said ring along a selected disc radius, said disc having arcuate slots cut Itherein adjacent the periphery thereof and defining resilient marginal edge portions for snugly engaging Said ring to hold the sarne in a selected position of adjustment, said snugly engaging edges being correspondingly tapered to prevent said ring from slipping off of said disc, and the outer peripheral edge of said ring having a thin stock receiving notch defined in the lower portion thereof.

References Cited in the lile of this patent UNITED STATES PATENTS 

